How Ransomware Takes Devices Hostage

May 02, 2016

Maybe the thought actually occurred to you that something was “phishy” about that link, but that’s so 30 seconds ago. You clicked and now your computer screen is locked. Behind that frozen screen lie your personal files — everything from photos to tax documents — all of it encrypted by a third party that promises to return access for a ransom, which is usually between $200 and $5,000, according to the FBI.

Encryption can be a tool for good and evil. It’s the safest way for an enterprise to keep information safe from prying eyes and sticky fingers, but unfortunately it’s relatively easy for a hacker — and not even a very clever one — to use it to force an ugly situation: your files are encrypted and can only be unlocked by the thief.

A recent newsworthy item takes its lead from the popular “Saw” horror series. If you get hit with this one, Billy the Puppet from the franchise pops up on your screen with the message: “I want to play a game with you.”

Think that invitation from Billy the Puppet sounds fun? Before you go looking for the jigsaw ransomware, also known as BitcoinBlackmailer.exe, let me assure you that it’s not. There are different versions, but they all say pretty much the same thing: “Your computer files have been encrypted. Your photos, videos, documents, etc….But, don’t worry! I have not deleted them, yet. You have 24 hours to pay 150 USD in Bitcoins to get the decryption key. Every hour, files will be deleted. Increasing in amount every time. After 72 hours all that are left will be deleted.”

If you get the jigsaw ransomware, don’t panic. As ZDNet (my source for the above script) points out, a company named Forcenet already solved the problem with simple reverse-engineering. According to those at Forcenet, “A genius malware author this is not, the use of C#/.NET makes it trivial to reverse engineer and analyse.”

Not Just an Inconvenience & Not Just a PC Problem

The point here is not whether or not a particular ransomware poses an extinction-level threat. Ransomware attacks are on the rise. According to Symantec’s 2016 Internet Security Threat Report, “crypto-style ransomware grew 35% in 2015.” In this report, Symantec warns that this often profitable approach, while adept at ensnaring PC users and branching out through network-connected devices, is increasingly targeting, “smartphones, Mac and Linux systems.”

In plain English: ransomware is a danger for anyone using a network-connected device. A former NSA employee recently released a tool for Mac users called RansomWhere, which detects when files are being encrypted on an Apple device and allows the user to stop it. That’s notable because, until now, most Apple users have been relatively unscathed by ransomware.

Adam Levin is co-founder of IDT911 and Credit.com, where this article originally appeared.